fix: 🐛 missed null check for showMaxErrors

Author: DmitryEfimenko

projects/ngx-errors/src/lib/errors-configuration.ts

@@ -24,7 +24,7 @@ export interface IErrorsConfiguration {
    *
    * `'formIsSubmitted'` - shows an error when parent form was submitted.
    */
-  showErrorsWhenInput: string;
+  showErrorsWhenInput?: string;
 
   /**
    * The maximum amount of errors to display per ngxErrors block.

projects/ngx-errors/src/lib/errors.directive.ts

@@ -93,7 +93,7 @@ export class ErrorsDirective implements AfterViewInit {
 
           const visible =
             !errorCouldBeHidden &&
-            (!this.config.showMaxErrors ||
+            (!this.config?.showMaxErrors ||
               visibleCount <= this.config.showMaxErrors);
 
           arr.push({ key, hidden: !visible });